Female slider biting the male one.. Help!

Question
QUESTION: I have two red eared sliders of about a year and a half old.
One is a male (4 inches) and the other is (3 inches).
The female has been biting the male's back legs recently.
The thing is she doesn't really bite him, it's like she's trying to remove a dead layer of skin or something. But she caused him slight injuries, though.
Also they don't seem like they hate each other at all. He doesn't even push her for biting him.
I tried separating them but I'm afraid that they might die because of that, I don't even know if that is possible.
I'd like to know why the female does that and what to do to keep both of them safe.
Thank you.

ANSWER: Hi Heba,

A 3" RES is too small to sex, so you may have a female, but it may also be an immature male.  A common reason for aggression is  being in a tank that is too small.  You didn't say what kind of setup you have your turtles in, and more information would certainly help, but I can at least tell you that two turtles the size of yours should be in a tank that's *at least* 70 gallons.  As adults, you will need a very large tank to house both of them together--150 gallons or bigger, or an outdoor pond, with a filter sized to handle a minimum of twice the tank's capacity.  Most health and behavioral issues with turtles are due to lack of room (also water quality, lack of UVB, and/or inadequate diet).

You can also separate the turtles if that works better for you.  Turtles have no emotional attachment to each other, and sometimes when you have a bullying situation separation is the best solution.  In that case, you still need to provide adequately sized tanks to ensure the health of the turtles.  

For more information on care, see:

http://www.redearslider.com/
http://www.austinsturtlepage.com/Care/caresheet-red_ear_slider.htm
http://www.austinsturtlepage.com/Care/care.htm
http://www.austinsturtlepage.com/Care/waterquality.htm
http://www.austinsturtlepage.com/Care/housing.htm

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QUESTION: It seems I'm definitely getting a bigger tank :D
So what do I need to do concerning the scratches on the male's legs?
They don't seem dangerous and nothing is unusual about them. I just want to know how to take care of him concerning this point.
I also heard that some people put their turtles in a salty water bath in similar situations.. I would appreciate your opinion about this.

ANSWER: If the scratches are fairly superficial, you can clean them daily with nolvasan (if you can get it) or a dilute betadine solution (dilute to the color of tea), then apply a topical antibiotic ointment and keep him dry for a couple of hours.  It would be best if you could separate them until you can set up the larger tank.  Make sure the new tank has a large basking area and plenty of hiding spots.  It may also help to put some live fish and plants in there, at least from time to time, for them to eat--it will give them something interesting to do.  This is another reason why having a large tank is a good idea, because you have more room for a more natural setup.  If at all possible, I would try to find a tank that will work for them at adult size.  That way, you won't have to buy a filter for a smaller tank and then upgrade later on, and your turtles will have plenty of room.  Good luck!

---------- FOLLOW-UP ----------

QUESTION: One more thing ...
I was told today (since I brought up the subject) that we had guests recently and someone fed the turtle that is biting the other a piece of crab!
I don't know if this is even suitable for them, but I was thinking though that it might be a reason for the biting thing?

Thank you.

Answer
Very unlikely, especially since you do apparently have them in too-small quarters.  Sometimes you get a turtle that's just a bully, but often it's simply due to overcrowding, which leads to heightened competition for resources (the best basking area, swimming area, food, etc.).  The bigger tank should make a difference.  Keep in mind that the smaller size I recommended is minimum, not optimum.  I always suggest getting the largest size feasible--bigger is better!